1972 dart - stopped running while at 50 mph ? no warning

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moparjon

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1972 dart 318 auto all stock . points . daily driver 20 years . never broke down until today . car warm and running great . i was cruising down the road at about 50 mph , real smooth . all of the sudden , i felt the car die . no warning , no sputtering , no surging , no noises , nothing , just cut off . i instinctively threw it into neutral , and tried to restart it while coasting . nothing , no start . i coasted into a nice parking lot , and first thought fuel pump . this is what i did so far , though maybe not in this order . fuel looked a little low in the filter . i checked the fuel pump by disconnecting the fuel line at the carb and cranking the motor . fuel came out in a , not fast , a little slow spurt then spurt , then spurt ( into a spare container mostly ) once or twice per second . so i think its getting fuel . plus pulling back the carb linkage it squirts inside the carb . i took the wire off the coil and put a spare wire in there and screwdriver at the other end , cranked the motor , had sparks . after putting coil wire back on i did the same to number one and number two wires from the distributor cap . did not see any spark , but mind you this is all in a rainy-ish snowstorm . not real bad but enough to be annoying . so some things were wet , and everything was done kinda rushed . i took the cap and rotor off and tapped the motor to get the points at the high point of the lobe to check gap , looked kinda off , so i reset gap with a feeler to 17-19 ish. , nothing . took the points out . a bit used/pitted . cap & rotor look good . replaced them a few months ago but was lazy a did not do the points . but they were on the front seat so i put the new ones in and gapped again , still nothing ( did not set dwell / no meter in the car ) . i also tried cranking with and without some of that gas , dribbled into the carb . i figured it should run with that even if the pump or filter failed , but did not . i was about to replace the ballast resistor when a flatbed pulled up nearby and did not have a car on it . since i did not have a cell phone with me ( new one in the mail supposedly coming tomorrow ) i took that as a sign from the mopar gods , and flagged the nice tow truck woman down . crazy lucky on that . at home , i replaced the ballast with another old one that tested good a long time ago . nothing . fuses under dash all good . car cranks great , plenty of battery . lights work and all that . i tried to get a dwell reading but something seemed off , like it wasn't reading . but i quit quickly cuz the situation and weather became too irritating , and it can wait . i did try to start it hours later cold , same thing cranks well , no start . i am thinking maybe the distributor went ? or voltage regulator ? timing chain ? i am not sure why it quit with no warning . soon , i plan on trying the dwell meter again , trying another ballast , rechecking spark from cap , cranking the motor to see if the rotor spins , and maybe looking in the valve cover to see if the rockers move . when i get a helper . i will look up how to check the regulator . did this ever happen to anyone ? what would be the likely cause ? any ideas or suggestions ? could it be the condenser ? trying to get a good plan together so i am ready when the weather is better . thank you .
 
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Sometimes you screw yourself by throwing parts at a problem, and can add problems you did not have

You started out well trying to diagnose the trouble, so a few random comments

1...Now that you have it home, "it might be" the cam drive slipped. If the engine is unknown and worn, that might be. Hoping that you have not moved the distributor, and if you had some idea where the timing was set, check the timing. Be aware, tho, that now that you have diddled the points it might have changed some. Points too far open advance timing, points worn more closed retard the timing. If it's WAY off and you have not twisted the dist, "might be" cam drive
2...When testing spark, it is important to be aware of several things, and to also estimate if you not only HAVE spark, but if it's "enough." So.........

A.....Power from key through the ballast to the coil is ONLY in run. If there is a problem in that circuit, the engine MAY fire during cranking and then die when key is released back to run
B....Power in cranking is supplied by the (usually brown) wire connected to the coil + side of the ballast, which comes from the IGN2 contact on the ignition switch. Just like the start contact, IGN2 is ONLY hot in "start" but it is a separate circuit from start

SO...........If you "check spark" by jumpering the starter relay.......you are using the "run" circuit and NOT the bypass circuit. THIS MEANS that voltage is greatly reduced, because you are powering the coil from the "run" circuit through the ballast, and as the charging system is not working, that voltage is now down to "battery" AND is further loaded down by the starter. You will be lucky to get 5V to the coil if doing so
SO............Try to check spark by using the KEY to crank. "RIG" a SOLID core wire to the coil tower (not radio resistor wire) and wire that to a test spark gap. Lisle makes a decent one that is adjustable, for about 10 bucks. You should get nice snappy blue spark at least 3/8" and more likely 1/2" long

IF YOU HAVE THAT don't waste time screwing with the points, etc.
2...Cap, rotor, wires..........Inspect cap for carbon tracking, dirt, moisture, same for rotor and LOOK FOR rotor "punch through." This is not very common with points. CHECK resistance of the coil wire with a meter. "Rule of thumb" for resistance wire is no more than 1000 ohms per foot, but if good, I've never seen one "that high." Usually much lower.
3...Fuel....Is it possible that somehow someone, either purpose or accident, dumped a bunch of water in the tank? Otherwise, there are procedures in the shop manual to test the pump for pressure and volume IF however the throttle causes the accelerator pump to provide a good stream of fuel down the throat, then it should at least have enough fuel in the carb to fire, cough, "do something."

"My gut." If it just quit AKA "as if the key was shut off" my suspect would be electrical and not fuel. But keep an open mind

Random:

Coils can "just fail" and they can fail/ get weak, and then "heal up" when they cool off. The condenser (in the distributor) can be intermittent as well

Carry an (or 2 or 3) alligator clip lead ---don't be afraid, EG to jumper power direct to coil + to see if you get spark or it will fire

Also, this problem could easily be our old friend ---bad terminals in the bulkhead connector
 
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You said you had spark so the ballast is good. New points and condensers suck so even new can be bad.
 
I had a 289 loose the timing chain teeth (nylon covered gears) at 65+ MPH no warning, no noise, just lost power.

I hope that is NOT what happened to you. I think 67dart273 is pointing you down the right path.
 
Here is an oldie but a goodie. Print it out and keep it in your car.
 

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Condenser.

I think you said you changed points but never the condenser.

If you jump the coil from battery +.. that bypasses the ballast, rules it out and allows you to test for spark. You can do all that and jump it at the starter switch/relay on the fender by the battery with a screwdriver.

Worst case the timing chain jumped.
 
Engine dying suddenly with no warning or rough running is usually electrical.
If the engine has a lot of mileage since the last tune up, check the points gap. It closes up with use.
 
Just start with the basics spark and fuel and troubleshoot it from the beginning so you dont miss anything. Ignition wise I can help you out if you have no spark.
looney-tunes-technical.gif


Hopefully you can get the "no run" condition again to find the actual problem with the car.
 
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just looking things over before anything else , looking at the wires . i noticed this mounted under and attached by a wire , to the coil . what is it ? what does it do ?



HPIM1528.JPG
 
A condensor as a radio static supressor, to keep your radio from being affected by static
 
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That is the radio noise supression capacitor/ condenser. Unless it is shorted, the engine should run fine. If it was shorted, it would be burning up the harness, or emitting smoke
 
67Dart273 said:
SO............Try to check spark by using the KEY to crank. "RIG" a SOLID core wire to the coil tower (not radio resistor wire) and wire that to a test spark gap. Lisle makes a decent one that is adjustable, for about 10 bucks. You should get nice snappy blue spark at least 3/8" and more likely 1/2" long
Click to expand...

do you mean a spare spark plug wire and attached it to the tester ? how can i tell if its solid core ? i think what i have , one says magnetic suppression , and another says static suppression mag wire stainless steel on it , yet another just says double silicone 7 mm . how bad would these be for the test ? thanks .
 
moparjon said:
do you mean a spare spark plug wire and attached it to the tester ? how can i tell if its solid core ? i think what i have , one says magnetic suppression , and another says static suppression mag wire stainless steel on it , yet another just says double silicone 7 mm . how bad would these be for the test ? thanks .
Click to expand...
Core wire?
Pull a cap wire off slide boot off, look
 
"zero ohms" resistance with a meter. Usually you can tell by examining the end terminal. The wire should be exposed, folded back, crimped into the terminal. "Blackish" looking "wire" is almost always resistance. You don't need to use a spark plug/ high tension wire. You can just use low voltage wire, "or even bare" but just keep it away from metal etc

It is likely that the "mag suppression" will be a wire type. They are usually some sort of spiral or other technology to help RFI
 
slight update . before going to the auto parts store to get the spark tester and alligator leads , i thought i should check a few things in case i need parts . just adding it here in case it points to something . i tested the condenser ( i think ) with a test light between the coil to dist. wire contact and its location on the coil , with key ON . i did not light up . meaning probably good according to something online . not 100% but if it did light up , it would mean a problem with it . "cleaned" the dist. wire and condenser contacts under the cap and the condenser body and its clamp with 320 sandpaper . tested the dist to coil wire for resistance . it was not getting a steady reading before cleaning the contacts with 320 , after it read a solid 0.2 - 0.3 ohms on the multimeter . not sure what it should be . ( later on i remembered the grommet for that wire on the dist. housing was kinda worn out . so maybe the wire is touching the housing . not sure if that would be enough to cause this condition . but i will look at it again later . ) i reset the points gap , and actually got a dwell reading this time . near 20 to 25 i think which i thought was close enough for now . after all these i hit the carb with a shot of starting fluid and still nothing . no start . then pumped the gas and tried in park and then again in neutral . still zero . next tested resistance of the coil to cap wire , but could not get a steady reading . it would just flash a number briefly before going back to 1 , but flashed anywhere from 565 to 998 . so i got the 74 valiant slant six started up , and after a short warming . took out its coil wire and put the darts in there . the valiant ran , seemingly just fine . i did not try the valiants coil wire in the dart , because i don't want that to get screwed up by whatevers going on with the dart . just paranoid probably , but not doing that . i checked the resistance of the ballast and got a reading of 1.7 and 1.8 , but , again , not sure what that is supposed to be . also , i grabbed the rotor and tried to turn it to check for play . did not move in one direction , did move a little/some the other way , and slowly returned a bit . not sure how fast it should spring back , but the dist. is old/original . i looked for a ground strap behind the motor , looking for one going to the firewall , but did not see any . however i did see this wire that looks really questionable down where it touches the trans ? where its been getting coated with oil and dirt for 50 years . what is that ? is it something with the neutral safety switch ? ( black wire , right of center , both photos ) thanks again , everyone .


HPIM1531.JPG




HPIM1530.JPG
 
MOPAROFFICIAL said:
Condenser.

I think you said you changed points but never the condenser.

If you jump the coil from battery +.. that bypasses the ballast, rules it out and allows you to test for spark. You can do all that and jump it at the starter switch/relay on the fender by the battery with a screwdriver.

Worst case the timing chain jumped.
Click to expand...

Yes ^^^

With the cap off look at the position of the rotor, bump the starter a few times and see it the position of the rotor changed. Checking for failed timing chain.

Put a big socket on the front crank bolt, rock the crank back and forth, watch the rotor to see how much slop you have in your timing chain. if there is lots of slop there it a good chance the timing chain jumped and threw valves and ignition out of time enough so it will not run anymore.
 
67Dart273 said:
SO...........If you "check spark" by jumpering the starter relay.......you are using the "run" circuit and NOT the bypass circuit. THIS MEANS that voltage is greatly reduced, because you are powering the coil from the "run" circuit through the ballast, and as the charging system is not working, that voltage is now down to "battery" AND is further loaded down by the starter. You will be lucky to get 5V to the coil if doing so
SO............Try to check spark by using the KEY to crank. "RIG" a SOLID core wire to the coil tower (not radio resistor wire) and wire that to a test spark gap. Lisle makes a decent one that is adjustable, for about 10 bucks. You should get nice snappy blue spark at least 3/8" and more likely 1/2" long
Click to expand...

ok , so i tried to check the timing , with a remote starter switch , but could not get the timing light to flash much at all , one or two random flashes , and nothing . tried two different timing lights a few times each , same result or nothing . i feel like i am doing something wrong . so i could not find a solid core wire , so i used what i have . i tried to check spark at first with the remote starter . zero from coil or plug wire number 1 . then i re read what you said a few times ( i takes me awhile ) and tried with the key . from what i could see looked like an ok to good spark , had the gap at about 3/8" , from looking between the bottom of the hood and cowl and with sun in the mix . heard a zap zap sparky sounds too . tried the same thing by putting the wire with tester in the cap where number 1 goes . got nothing , no spark , no happy sounds . then pulled the cap , pressed the remote starter , rotor is spinning , points are opening and closing , but no sparky goodness from those either .
 
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moparjon said:
ok , so i tried to check the timing , with a remote starter switch , but could not get the timing light to flash much at all , one or two random flashes , and nothing . tried two different timing lights a few times each , same result or nothing . i feel like i am doing something wrong . so i could not find a solid core wire , so i used what i have . i tried to check spark at first with the remote starter . zero from coil or plug wire number 1 . then i re read what you said a few times ( i takes me awhile ) and tried with the key . from what i could see looked like an ok to good spark , from looking between the bottom of the hood and cowl and with sun in the mix . heard a zap zap sparky sounds too . tried the same thing by putting the wire with tester in the cap where number 1 goes . got nothing , no spark , no happy sounds . then pulled the cap , pressed the remote starter , rotor is spinning , points are opening and closing , but no sparky goodness from those either .
Click to expand...

Direct hot wire to the positive side of your coil taking off the connection from the ballast resistor line to the + side of the coil. Make sure the - wire coming from the distributor is going to the negative side of the coil - .

Now fire it up.
 
67Dart273 said:
2...Cap, rotor, wires..........Inspect cap for carbon tracking, dirt, moisture, same for rotor and LOOK FOR rotor "punch through." This is not very common with points. CHECK resistance of the coil wire with a meter. "Rule of thumb" for resistance wire is no more than 1000 ohms per foot, but if good, I've never seen one "that high." Usually much lower.
Click to expand...

what is rotor punch through ? and what am i looking for ? i don't know what that is . as for the coil wire , i

moparjon said:
tested resistance of the coil to cap wire , but could not get a steady reading . it would just flash a number briefly before going back to 1 , but flashed anywhere from 565 to 998 . so i got the 74 valiant slant six started up , and after a short warming . took out its coil wire and put the darts in there . the valiant ran , seemingly just fine .
Click to expand...

i just now attached the dist. cap end of the coil wire to alligator clips then the spark tester . good spark .
 
George Jets said:
Direct hot wire to the positive side of your coil taking off the connection from the ballast resistor line to the + side of the coil. Make sure the - wire coming from the distributor is going to the negative side of the coil - .
Click to expand...

when you say , direct hot wire , do you mean run a wire between the positive battery terminal to the coil positive terminal ?
 
moparjon said:
when you say , direct hot wire , do you mean run a wire between the positive battery terminal to the coil positive terminal ?
Click to expand...

Yes, that is Hot Wiring the Coil.

Don't leave it hooked up for a long time as it will heat up the coil with the full 12 volts. But you can try and start it to get it running.
 
George Jets said:
Yes, that is Hot Wiring the Coil.

Don't leave it hooked up for a long time as it will heat up the coil with the full 12 volts. But you can try and start it to get it running.
Click to expand...

hmm , pretty much just burned up the wire in seconds , probably need a bigger wire . wait , maybe i went to the wrong terminal . i should sleep more .
 
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